The present invention relates to a facade structure having an inner bearer for at least one plate element. Holders engage behind the plate element in its edge region, and they are mounted in the bearer so as to be adjustable relative thereto.
One embodiment of this general type is disclosed in German Offenlegungsschrift No. 3,439,436. Here, the bearer is shown as a post or transom comprising an aluminum section. The plate element is an insulating glass unit, having in its edge region inserted U-shaped outwardly open sectional rails forming a continuous frame or alternatively being inserted only in spaced locations. The insulating glass unit is supported on the post section via a glass contact gasket. Fixed to the post section are holders that form a row and are equipped, at their free ends, with flanges which engage into the U-shaped sectional rails. These flanges are set back from the outer faces of the insulating glass panes; the space formed thereby is filled with a sealing compound, so as to form a smooth outer surface for the facade. Each holder is equipped with a hammerhead-shaped turned fastening part which can be introduced into a T-shaped slot provided on the outer face of the post section and which can be secured by means of a quarter turn. The opposite end of the holder has the flange which at the same time engages into sectional rails of two insulating glass units located next to one another.
The holder is rotatable about its longitudinal center axis relative to the post section. The depth of engagement of the flange into the U-shaped sectional rail of the insulating glass unit depends on its position in relation to the holder. However, on the one hand, this position cannot be foreseen exactly when the facade structure is produced, and, on the other hand, it can vary during the "operation" of the facade structure. Because of the customary tolerances for glass blanks which are of the order of .+-.2 mm, the pane edge, behind which the holder engages, can be nearer the holder or farther away from it. Corresponding differences also arise under the effect of temperatures caused by the weather, which result in different longitudinal expansions of the glass and the metal sections. Under the effect of wind loads pronounced deflection of the insulating glass unit and consequently a reduction in its length or width can occur. A further disadvantage of the structure described above is that the holders each exert a point load on the edge of the inwardly facing insulating pane, behind which they engage. The blank tolerances, which can amount to as much as 3 mm where triple insulating glass is concerned, plus the longitudinal expansion of the aluminum frame, plus the effect of wind load, have to be taken into account in the structure from the outset, and this disadvantageously leads to large batch widths.